The present disclosure relates to an image sensor, a control method of the image sensor, and an imaging apparatus. In more detail, the present disclosure relates to an image sensor which includes pixels for detecting a phase difference, a control method of the image sensor, and an imaging apparatus.
In related art, a phase difference detection system is known as one technique for focus detection in an imaging apparatus. This phase difference detection system is a system which detects a focal point from a phase difference of a signal output by a pair of light receiving elements. In an imaging apparatus which does not include a mirror guiding light to the light receiving elements for this phase difference detection, pixels for detecting the phase difference (hereinafter, called “phase difference pixels”) may be arranged on a light receiving surface along with other pixels (hereinafter, called “normal pixels”). In the case where an image is captured and a phase difference is detected in such an imaging apparatus, an image process, such as a de-mosaic process, is usually performed by reading pixel values of all the pixels, and then interpolating pixel values of the phase difference pixels in these pixel values. Further, the detection of a phase difference is performed by separating the pixel values of the phase difference pixels from the pixel values of all the read out pixels.
In an imaging apparatus in which such phase difference pixels and normal pixels are arranged, the response of displaying and focusing the image improves as the time from the start of imaging until the end of the image process and phase difference detection process shortens. Accordingly, in order to shorten the time until the end of the image process and phase difference detection process, a control method has been proposed (for example, refer to JP 2011-101325A) which performs, for example, reading by thinning lines, such as reading only one out of three lines, when reading the pixel values.